Strain gages are employed as a basic movement-electric signal transducer in devices for measuring force, pressure and flexure, to name only a few. Although metals (e.g., chromium) were primarily relied upon at first, semiconductor materials offer certain advantages thereover, such as greater gage factor and smaller size. The temperature characteristics of semiconductors have made them not completely satisfactory, however, for precision strain gage applications.
In a frequently encountered manner of use, the strain gage is electrically arranged as a bridge (e.g., Wheatstone bridge), and it is important that a positive thermal sensitivity shift (TSS) be maintained. Moreover, it is desirable to be able to control the temperature coefficient of resistance (TCR) of the gage material within a narrow range.